It happened on the Ballycumber Road in Clara, Co Offaly, shortly after 6pm. It is understood she was with her brother (8) at the time.

The two had apparently followed a dog on to the road when the girl was hit. She lost consciousness at the scene and was taken to the Midland Regional Hospital in Tullamore in a serious condition. A HSE spokeswoman said the child was in a stable condition.

The children lived in the Westwood Park area. Gardai sealed off the road as a crash scene examination was carried out.